Post-harvest orchard management

30 January 2015 | John Wilton, AgFirst | Australian Fruitgrower article

The period from harvest to leaf fall is an important recovery phase for apple trees. John Wilton explains how post-harvest irrigation, nutrition, pruning and branch training can be used to rebuild nutrient and carbohydrate reserves and prepare the orchard for strong flowering, fruit set and canopy performance in the following season.

Because this period coincides with a major root flush, adequate soil moisture is essential. Where soils are dry, irrigation is needed to support active roots and nutrient uptake. Wilton notes that many modern varieties are deliberately run at low nitrogen levels before harvest to improve colour, so post-harvest nitrogen replenishment becomes important once the crop has been picked.

The article discusses foliar urea as an efficient post-harvest nitrogen strategy and lists signs of low nitrogen status such as poor fruit set, small fruit relative to crop load, pale foliage and early leaf fall. It also points growers toward drainage and water-stress problems that can limit nutrient uptake even when fertiliser is available.

Post-harvest is also a useful timing for removing strongly shading branches in vigorous blocks and for branch training in developing orchards. The overall approach is to finish the season by restoring tree reserves, improving light distribution and setting up productive fruiting wood for the next crop.